60% (1997)

63% (1990)

56% (1996)

44% (1988)

67% (1992)

63% (1990)

25% (1996)

63% (1991)

67% (1988)

55% (1993)

50% (1996)

43% (1995)

47% (1995)

30% (1992)

43% (1990)

72% (1996)

55% (1994)

46% (1998)

24% (1991)

40% (1990)